Recording medium driving device

ABSTRACT

A disc drive device for driving a disc held in a cartridge having a movable shutter includes a readout head radially movable on the disc and mounted on a chassis that also mounts a cartridge holder, a disc table on which the disc is loaded, a shutter mechanism for operating the shutter, and a retainer mechanism for holding the shutter open by the shutter mechanism when the disc is loaded on the disc table.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of Application No.10/258,993 filed Oct. 31, 2002, now U.S. Pat. No. 6,934,957, thedisclosure of which is hereby incorporated by reference herein, which isa national phase entry under 35 USC § 371 of International ApplicationNo. PCT/JP02/02383 filed Mar. 13, 2002, published in Japanese, whichclaims priority from Japanese Application No. 2001-071134 filed Mar. 13,2001.

TECHNICAL FIELD

The present invention relates to a recording medium driving device forrecording information signals and for reproducing the signals for arecording medium. More particularly, the present invention relates to arecording medium driving device in which a recording medium held by aholder is ejected by an ejection lever.

BACKGROUND ART

There are recording medium driving devices for reproducing informationsignals recorded on the disc-shaped recording mediums. In certain onesof the recording medium driving devices, a slider held by a holder ismoved in one direction when a recording medium is held on the holder tolower the holder to load the recording medium on the loading unit, whilethe slider is moved in the opposite direction to elevate the holder toeject the recording medium from the holder by an ejection lever.

As typical of this sort of the recording medium driving device, there isknown a device shown in FIGS. 1 to 5. With this driving device, upwardlyopened guide grooves 102, 102 are formed in both lateral sides of achassis 101. In these guide grooves 102, 102, there are slidablysupported a pair of rearwardly positioned support pins 104, 104 providedon both lateral surfaces of a holder 123, there being another pair offorwardly positioned similar support pins provided on both lateralsurfaces of the holder 123.

On the holder 123, there is mounted a slider 105 for sliding in thefore-and-aft direction. The slider 105 includes lateral surface sections106, 106 and a connecting portion 107 interconnecting the lateralsurface sections 106, 106. In the lateral surface sections 106, 106,there are cam grooves 108, 108 which are spaced apart from each other inthe in the fore-and-aft direction. In the cam grooves 108, 108, thesupport pins 104, 104 of the holder 123 are supported for slidingmovement. A slider biasing spring 109 is mounted under tension betweenthe lateral surfaces 106, 106 of the slider 104 and a rearward portionof the chassis 101 for biasing the slider 105 rearwards.

At the rear end of the chassis 101, there is mounted a lever supportinglug 110, and an ejection lever 111 is rotatably mounted at the foremostpart of the supporting lug 110. A lever biasing spring 112 is mountedunder tension between the ejection lever 111 and the holder 123 forbiasing the ejection lever 111 in a direction indicated by arrow R1 inFIG. 1. The foremost part of the ejection lever 111 is provided with anoperating piece 113 which is bent downwards.

Before insertion of the recording medium into the holder 123, theejection lever 111 includes a control edge 114 engaged with a matingcontrol edge 116 of the slider 105 so that the slider 105 is held at itsforemost movement stroke end (see FIGS. 1 and 2).

When a recording medium 117 is inserted from the forward side into theholder 123, the operating piece 113 of the ejection lever 111 is thrustrearwards by the recording medium 117, so that the ejection lever 111 isrotated in the direction indicated by arrow R2 against the bias of thelever biasing spring 112 (see FIG. 3). When the ejection lever 111 isrotated in the direction indicated by arrow R2 in FIG. 3, the controledge 114 is disengaged from the mating control edge 116, so that theslider 105 is slid rearwards by the slider biasing spring 109 (see FIG.4).

When the slider 105 is moved rearwards, the positions of the supportpins 104, 104 of the holder 123 in the cam grooves 108, 108 are changed,such that the rearward side support pins 104, 104 are moved within theguide grooves 102 of the chassis 101 to cause descent of the holder 123(see FIG. 5). With the descent of the holder 123, the recording medium117 which it holds is loaded on a loading unit, not shown, therebysetting up a state enabling the reproducing operation of informationsignals for the recording medium 117. The slider 105 is moved rearwardsat this time as the mating control edge 116 has a sliding contact with aportion of the ejection lever 111. The ejection lever 111 has itsportion engaged with the mating control edge 116 of the slider 105,moved rearwards, so that the ejection lever is held at the end of therotation indicated by arrow R2.

When the reproducing operation comes to a close, such that an ejectionbutton, not shown, is actuated, a driving motor, not shown, is rotatedto cause forward movement of the slider 105 under the driving force ofthe motor against the biasing force of the slider biasing spring 109.

When the slider 105 is moved forwards, the positions of the support pins104, 104 of the holder 123 in the cam grooves 108, 108 are changed, suchthat the holder 123 is lifted by the rearward side support pins 104, 104being moved in the guide groove 102 b of the chassis 101.

When the slider 105 has been moved forwards by the ejection lever 111,the ejection lever 111 is rotated by the lever biasing spring 112 in adirection indicated by arrow R1. Consequently, the recording medium 117is thrust forwards and ejected out of the holder 123 by the operatingpiece 113 of the ejection lever 111.

When the slider 105 is moved to a forward side preset position, therotation of the driving motor ceases. The slider 105 is moved rearwards,under the force of the slider biasing spring 109, and the mating controledge 116 is engaged with the control edge 114. of the ejection lever111, which is positioned at the end of the movement stroke in thedirection R1. The slider 105 again is held at the forward end in therange of movement.

In the above-described recording medium driving device of the relatedart, described above, the lever biasing spring 112 for biasing theejection lever 111 and the slider biasing spring 109 for biasing theslider 105 are required, with the consequence that the number ofcomponents is correspondingly increased. When inserting the recordingmedium 117 into the holder 123, the slider 105, moved towards rear, hasa sliding contact with the ejection lever 111. Since the lever biasingspring 112 at this time is in the fully stretched state, the frictionalresistance between the slider 105 and the ejection lever 111 is large,with the result that the slider 105 and the ejection lever 111 arelowered in durability. Moreover, the load imposed on the driving motorfor ejecting the recording medium 117 is increased in an amountcorresponding to the increased frictional resistance between the slider105 and the ejection lever 111, thus increasing the power consumption.

Another instance of the recording medium driving device is a recordingand/or reproducing apparatus for recording and/or reproducinginformation signals for the recording medium. In a certain type of thisrecording and/or reproducing apparatus, there is such an apparatus inwhich, when the recording medium is held by the holder, the slider heldby the holder is moved in one direction to lower the holder to load therecording medium on the loading unit, and in which, when the slider ismoved in the opposite direction, the holder is elevated, at the sametime as the recording medium is ejected by the ejection lever from theholder.

As this sort of the recording and/or reproducing apparatus, there issuch apparatus constructed as shown in FIGS. 6 and 7.

The recording and/or reproducing apparatus, shown in FIGS. 6 and 7,includes a holder 201 movable vertically relative to the chassis.

The holder 201 is movable vertically relative to the chassis, not shown.A cam lever 202 is supported by the holder 201 for sliding in thefore-and-aft direction. The cam lever 202 includes a cam 203 and avertically extending support leg 204, which support leg 204 is supportedfor movement in the up-and-down direction in a support opening 205formed in the chassis.

A supporting piece 206 is provided on the upper surface of the holder201. The supporting piece 206 rotationally supports a head shift lever207. The head shift lever 207 is provided with a mating operatingportion 208 that is in sliding contact with the cam 203 of the cam lever202.

A pickup includes a mounting portion 209. On the upper surface of themounting portion 209, there is mounted a rear end of a head mountingplate 211, the distal end of which carries a magnetic head 210. The headmounting plate 211 is formed of an elastic material.

The above-described holder 201 and the chassis etc are arranged withinan outer casing of the recording and/or reproducing apparatus. A topplate 213 of the outer casing is provided on top of the holder 201.

FIG. 6 shows the state in which the magnetic head 210 is at a firstretreat position. During reproduction of information signals from arecording medium, for example, the magnetic head 210 is not in use, sothat the magnetic head 210 is retreated from the recording medium heldon the holder 201, and is at the first retreat position. At this time,the mating operating portion 208 of the head shift lever 207 is engagedwith the uppermost end of the cam 203 of the cam lever 202, with thehead mounting plate 211 being lifted by the head shift lever 207 in aforwardly descending state. The magnetic head 210 is at a position ofbeing retreated from the recording medium held by the holder 201 rightabove the upper surface of the holder 201.

When the information signal reproducing operation for the recordingmedium has been finished, such that the recording medium is ejectedforwards from the holder 201, the holder 201 is moved upwards from thestate of FIG. 58, while the cam lever 102 is also moved upwards inunison with the holder 201 (see FIG. 7).

When the holder 201 and the cam lever 202 are moved upwards, therelative position between the head shift lever 207 and the cam 203 isnot changed. However, since the cam 203 is at substantially the sameheight level as the mounting portion 209, the magnetic head 210 is movedto a second retreat position with a rising gradient in the forwarddirection, so that the magnetic head 210 is at a higher height levelthan the above-mentioned first retreat position (see FIG. 7).

In the above-described recording and/or reproducing apparatus of therelated art, the head mounting plate 211, which has been lifted with theforwardly descending gradient, is lifted with a forwardly risinggradient when the recording medium is ejected from the holder 201. As aconsequence, in the recording and/or reproducing apparatus of therelated art, there is required a large space between the upper surfaceof the holder 201 and the outer casing 213 of the outer casing, in orderto permit the magnetic head 210 to be moved between the first and secondretreat positions, thus increasing the overall thickness of therecording and/or reproducing apparatus.

Moreover, the recording medium driving device is designed for recordingand/or reproducing information signals for the disc-shaped recordingmedium loaded on the disc table. This sort of the disc recording and/orreproducing apparatus includes an ejection mechanism for ejecting thedisc-shaped recording medium loaded on the disc table on completion ofthe recording and/or reproduction of the information signals, and a headmovement mechanism for causing movement of the magnetic head, adaptedfor applying the magnetic field to the disc-shaped recording mediumduring recording, in a direction into contact with or away from thedisc-shaped recording medium.

In certain versions of this sort of the recording medium driving device,both the operations of the ejection mechanism and the head movementmechanism are operated by the driving power of a sole driving motor, inorder to make common use of the sole driving motor. In a disc recordingand/or reproducing apparatus of the related art, in which a sole drivingmotor is used in common, a slider is supported for movement on a holderholding a disc-shaped recording medium, and is moved a first movementamount in one direction with respect to the holder. On completion of theloading, the slider is moved by a second movement amount relative to theholder in the same sole direction by the driving motor to actuate thehead movement mechanism, and the magnetic head is moved in a directionof contacting with the so loaded disc-shaped recording medium to set upthe recording mode.

Consequently, when the recording of the information signals has come toa close, the driving motor is rotated in reverse, while the slider ismoved relative to the holder in a direction opposite to theaforementioned one direction by a second amount of movement, with themagnetic head being moved in a direction away from the disc-shapedrecording medium to cancel the setting of the recording mode. When thedisc-shaped recording medium is to be ejected in the canceled state ofthe setting of the recording mode, rotation of the driving motor iscontinued to cause the slider to be moved relative to the holder by thefirst amount of movement in an opposite direction to the aforementionedone direction to cause the operation of the ejection mechanism.

In the above-described driving device of the related art, when therecording of the information signals has come to a close and thedisc-shaped recording medium is to be ejected, the slider is moved inthe same direction to actuate the ejection mechanism or the headmovement mechanism, so that a movement stroke corresponding to the sumof the first and second amounts of movement is required.

As a consequence, the recording medium driving device is increased insize by an amount corresponding to the increased amount of the slidermovement stroke.

There is also a recording medium driving device adapted for driving a.disc cartridge in a casing member of which a disc-shaped recordingmedium is rotatably mounted and in which a shutter is also supported forsliding on the casing member.

In such driving device, the shutter is slid by a shutter opening/closingmechanism, usually at the time of inserting the disc cartridge into theholder to open a through-hole formed in the casing member to permit thelaser light to be illuminated from a light source of the optical pickupto the disc-shaped recording medium contained in the casing member.

The shutter slid is held at an open position, however, if the shutter isvibrated in this case to produce resonant vibrations, it may beimpossible to maintain optimum reproducing operations for thedisc-shaped recording medium of the disc driving device.

In order to combat this inconvenience, a certain disc driving device ofthe related art includes retention means, such as a spring plate, on aportion of an outer casing, in the inside of which a holder or a chassisis mounted, such that, when the disc-shaped recording medium is loadedon the disc table, the shutter is retained by this retention means tosuppress the vibrations which will otherwise be produced.

In the recording medium driving device of the related art, in which theretention means are provided at a portion of the outer casing thereof,the vibrations transmitted from outside to the disc driving device tendsto be transmitted to the shutter through the retention means, with theresult that vibrations cannot be suppressed sufficiently.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide a novel recordingmedium driving device which overcomes the problems the above-describedrecording medium driving device of the related art suffers.

It is another object of the present invention to provide a recordingmedium driving device in which it is possible to reduce the number ofcomponents and to improve durability of the respective components aswell as to reduce the power consumption.

It is still another object of the present invention to provide arecording medium driving device in which collision between a recordingmedium inserted into or ejected from the holder and the magnetic headmay be avoided to reduce the size of the apparatus itself.

It is a further object of the present invention to provide a recordingmedium driving device in which the operations of the ejection mechanismand the head movement mechanism are carried out by a sole driving motorto reduce the size of the apparatus itself.

It is yet another object of the present invention to provide a recordingmedium driving device in which vibrations of the shutter ma beefficiently suppressed to assure n optimum operation.

For accomplishing the above object, the present invention provides arecording medium driving device including a loading unit for loading arecording medium thereon, and a holder movably carried by a chassis,with the holder holding the recording medium and transporting therecording medium between an insertion/ejection position of inserting orejecting the recording medium and a loading position of loading therecording medium on the loading unit. The recording medium drivingdevice also includes an ejection lever for ejecting the recording mediumfrom the holder, a slider movable in a direction of inserting therecording medium into the holder and in a direction of ejecting therecording medium from the holder, with the slider causing the holder tobe moved to the loading position when the slider is moved in theinserting direction, with the slider causing the holder to be moved tothe insertion/ejection position when the slider is moved in the ejectingdirection. The recording medium driving device also includes a springmember provided between the ejection lever and the slider for biasingthe ejection lever in a direction of ejecting the slider from the holderand for biasing the slider in the inserting direction.

Preferably, the ejection lever is rotatably mounted at a corner of thechassis and includes at its one end an operating portion for ejectingthe recording medium from the holder, while including at its other end acontrol portion for controlling the slider towards the ejectingdirection. When the recording medium is not loaded on the recordingmedium driving device, the slider is arranged in the ejecting directionand the operating portion of the ejection lever is biased and rotated inthe ejecting direction, the controlling portion engaging with acontrolled portion of the slider to control the slider in the ejectingdirection.

In the recording medium driving device according to the presentinvention, when the recording medium is introduced into the holder, theoperating portion of the ejection lever thrusting the forward end of therecording medium is inserted so that the operating portion is rotated inthe inserting direction. The controlling portion is rotated with suchrotation to be disengaged from the controlled portion so that the slideris moved in the inserting direction under the bias of the spring member.The slider has a portion thereof engaged with a portion of the other endof the ejection lever to hold the ejection lever at the insertingdirection. The holder is moved to the loading position with movement ofthe slider in the inserting direction for loading the recording mediuminserted in the holder to the loading position.

Preferably, the recording medium driving device further includesejection controlling means for causing the slider to be moved in theejecting direction responsive to a user's command. The slider is movedin the ejecting direction under control by the ejection controllingmeans to cause the holder to be moved to the insertion/ejection positionand to extend the spring member. The operating portion of the ejectionlever is moved in the ejecting direction to eject the recording mediumby a portion of the slider being disengaged from a portion of theopposite end of the ejection lever with movement of the slider. Thecontrolling portion of the ejection lever is re-engaged with thecontrolled portion of the slider to control the slider at the ejectingdirection.

The present invention also provides a recording medium driving deviceincluding a loading unit for loading a recording medium thereon, and aholder for holding the recording medium, which holder is movable betweenan insertion/ejection position inserting/ejecting the recording mediumand a loading position loading the recording medium on the loading unit.The recording medium driving device also includes an ejection lever forejecting the recording medium from the holder at the inserting/ejectingposition, and a slider movable in a direction of inserting the recordingmedium into the holder and in a direction of ejecting the recordingmedium from the holder. When the slider is moved in the insertingdirection, the slider causes the holder to be moved from theinserting/ejecting position. towards the loading position. When theslider is moved in the ejecting direction, it causes the holder to bemoved from the loading position to the insertion/ejection position. Therecording medium driving device also includes a head for recordinginformation signals on the recording medium, a head shift lever forcausing the head to be moved in a direction of contacting with andseparating from the recording medium, and a cam lever carried by theholder for movement in the inserting direction and in the ejectingdirection. The cam lever operates the head shift lever. The head isretreated to a first retreat position receded from the recording mediumas held by the holder, when the recording medium is ejected from theholder positioned at the insertion/ejection position under the drivingforce of the driving motor. The head is also retreated to a secondretreat position receded from the recording medium when informationsignals are reproduced from the recording medium at the loadingposition. The holder is moved to the insertion/ejection position whenthe recording medium is ejected from the holder by a manual operation bya user during the recording of information signals on the recordingmedium in the loading unit. Also, the head is retreated to a thirdretreat position receded from the recording medium ejected from theholder. In the first, second and third retreat positions, the relativeposition between the head and the holder relative to the contacting orseparating direction is substantially the same.

In this recording medium driving device, the cam lever includes a firstcam portion for operating the head shift lever to cause the head to bereceded to the first retreat position receded from the recording mediumheld by the holder when the recording medium is ejected from the holderat the insertion/ejection position, under the driving force of thedriving motor, a second cam portion for operating the head shift leverso that, when the information signals are reproduced at the loading unitfrom the recording medium, the head will be receded to the secondretreat position receded from the recording medium, and a third camportion for operating the head shift lever so that, when the recordingmedium is ejected by a manual operation of the user when informationsignals are being recorded on the recording medium in the loading unit,the holder will be moved to the insertion/ejection position, the headbeing receded to the third retreat position in which the head is recededfrom the recording medium.

The present invention also provides a recording medium driving deviceincluding a loading unit for loading a disc thereon, a head movementmechanism for causing a recording head, recording the informationsignals on a disc loaded on the loading unit, to be moved in a directionof contacting with or separating from the disc, an ejection mechanismfor ejecting the disc loaded on the loading unit to outside, a drivinggear rotated in one direction or in the other direction by a drivingmotor, a joint lever which, when the driving gear is rotated in onedirection, is moved through the driving gear to operate the ejectionmechanism, and a driving lever which, when the driving gear is rotatedin the other direction, is moved through the driving gear to operate thehead movement mechanism.

Preferably, the recording medium driving device further includes adriving power transmitting portion provided to the driving gear fortransmitting the driving power of the driving motor, and an operatinglever which, when the driving gear is rotated in the other direction, isthrust by the driving power transmitting portion to impart the drivingpower of the driving motor to the driving lever, and which, when thedriving gear is rotated in the one direction, is thrust by the drivingpower transmitting portion to be receded from the trajectory of thedriving power transmitting portion.

The present invention also provides a recording medium driving devicefor driving a disc cartridge including a disc and a cartridge having thedisc held therein, with the disc cartridge opening/closing aninformation recording surface of the disc by a shutter movably mountedin the cartridge. The recording medium driving device includes readoutmeans movable along the radius of the disc for reading out theinformation from the information recording surface of the disc, achassis on which the readout means is mounted for movement radially ofthe disc, a holder movably mounted on the chassis for holding the disccartridge, a disc table for loading a disc in the disc cartridge as heldby the holder, a shutter opening/closing mechanism for opening/closingthe shutter, and retention means provided on the chassis or the. holderfor holding the shutter opened by the shutter opening/closing mechanismwhen the disc is loaded on the disc table.

The retention means may be a spring plate member having one end mountedto the chassis and having retention means at the other end. Theretention means is resiliently contacted with the shutter.

The retention means may be a detection switch having a mating operatingshaft resiliently contacted with the shutter when the holder is moved.By the mating operating shaft being operated by resilient contact withthe shutter, the detection switch detects whether or not writing on aninformation recording surface of the disc is inhibited.

Other objects, features and advantages of the present invention willbecome more apparent from reading the embodiments of the presentinvention as shown in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 show the operation of a recording and/or reproducing apparatus ofthe related art, and is a plan view showing the state prior to rotationof the ejection lever,

FIG. 2 is a side view thereof, showing the state prior to descent of theholder,

FIG. 3 is a plan view thereof, showing the state prior to descent of theholder,

FIG. 4 is a plan view thereof, showing the state in which the ejectionlever has been rotated to shift the slider backwards, and

FIG. 5 is a side view thereof showing the state in which the holder hasbeen lowered.

FIG. 6 shows the operation of another recording and/or reproducingapparatus of the related art, and is a side view, shown partially incross-section, and showing the state in which, when the holder has beenlowered, the magnetic head has retreated, and

FIG. 7 is a schematic enlarged side view, shown partially incross-section, and showing the state in which, when the holder islifted, the magnetic head has been retreated.

FIG. 8 is a perspective view showing the recording and/or reproducingapparatus to which the present invention is applied, and a disccartridge.

FIG. 9 is a perspective view showing the chassis and respective portionsor units supported by the chassis.

FIG. 10 is a perspective view showing the inner structure of a discrecording and/or reproducing apparatus according to the presentinvention.

FIG. 11 is a plan view, partially cut away, and showing various portionsor units supported by the chassis

FIG. 12 is a plan view showing a holder and a cam lever held by theholder.

FIG. 13 is an enlarged side view showing the holder and the cam leverheld by the holder.

FIG. 14 is a plan view showing the holder and the cam lever as well asthe slider held by the cam lever.

FIG. 15 is an enlarged side view showing the holder and the cam lever aswell as the slider held by the cam lever.

FIG. 16 is a perspective view showing a chassis.

FIG. 17 is a perspective view showing the holder, partially cut away.

FIG. 18 is a plan view showing a head shift lever.

FIG. 19 is a side view showing the head shift lever.

FIG. 20 is a plan view showing a cam lever.

FIG. 21 is a side view showing the cam lever.

FIG. 22 is a plan view showing a slider.

FIG. 23 is a left side view showing the slider.

FIG. 24 is a right side view showing the slider.

FIG. 25, showing a sequence of assembling the slider on the holder, is aside view showing the state in which a holder supporting pin is engagedin a lower horizontal portion of a slider cam groove,

FIG. 26 is a side view showing the state in which the slider is movedforwards and the holder supporting pin is engaged in the upperhorizontal portion of the slider cam groove,

FIG. 27 is an enlarged side view showing the state in which the sliderhas been placed on the holder, and

FIG. 28 is an enlarged side view showing the state in which theassembling of the slider on the holder has been completed.

FIG. 29 is a plan view showing an ejection lever.

FIG. 30 is a front view thereof.

FIG. 31 is a side view showing a joint lever.

FIG. 32 shows a disc detection switch and is a cross-sectional viewshowing the switch in the non-operated state, and

FIG. 33 is a cross-sectional view showing the switch in the operatedstate.

FIG. 34 is a plan view showing a driving lever.

FIG. 35 is a plan view showing a limit lever.

FIG. 36 is a plan view showing a converting lever.

FIG. 37 is a cross-sectional view showing the converting lever.

FIG. 38 is a bottom view showing the limit lever and an operating leversupported by the limit lever.

FIG. 39 is a plan view showing the operating lever.

FIG. 40 is an enlarged cross-sectional view showing the state ofmounting a spring plate member to the chassis.

FIG. 41 is a block diagram showing the structure of a portion of thedisc recording and/or reproducing apparatus.

FIG. 42 shows the operation of the disc recording and/or reproducingapparatus and is a plan view showing the initial state prior tooperation of respective portions or units,

FIG. 43 is a side view showing the initial state prior to operation ofrespective portions or units, with a joint lever being omitted, and

FIG. 44 is a side view showing the initial state prior to operation ofthe respective portions or units.

FIG. 45 is a plan view showing, of the constituent elements carried bythe lower chassis surface, the initial state prior to operation ofrespective portions or units of the disc recording and/or reproducingapparatus, and

FIG. 46 is a side view, shown partially in cross-section, and showingthe initial state prior to operation of the respective portions or unitsas the position relationships between the cam lever and the magnetichead.

FIG. 47 is a plan view showing the state in which a disc cartridge isbeing introduced into a cartridge holder.

FIG. 48 is a plan view showing the state in which the slider has beenmoved to the rear end of its movement stroke.

FIG. 49 is a side view showing the state of descent of the holder, withthe joint lever being omitted.

FIG. 50 is a side view, shown partially in cross-section, and showingthe state in which a disc cartridge has been introduced into thecartridge holder and the holder is being lowered, as the positionrelationships between the cam lever and the magnetic head.

FIG. 51 is a side view, shown partially in cross-section, and showingthe state of completion of descent of the holder, as the positionrelationships between the cam lever and the magnetic head.

FIG. 52 is a cross-sectional view showing the state in which a springplate member used as retention means has been resiliently contacted by ashutter.

FIG. 53 is a cross-sectional view showing the state in which a matingoperating shaft of a disc detection switch used as retention means hasbeen resiliently contacted by the shutter.

FIG. 54 is a plan view showing, of the constituent elements supported bythe lower surface of the chassis, the state in which a driving gear hasbeen rotated in a first direction and the limit lever has been moved tothe forward side end of the movement stroke, while the driving lever hasbeen moved to the rear movement stroke end.

FIG. 55 is a side view showing the state in which the magnetic head hasbeen inserted via a head inserting opening in the holder, as theposition relationships between the cam lever and the magnetic head.

FIG. 56 is a plan view showing, of the constituent elements carried onthe lower chassis surface, the state in which the driving gear has beenrotated in a second direction, the limit lever has been moved to therear movement stroke end and the driving lever has been moved to theforward movement stroke end.

FIG. 57 is a side view showing the state in which, when the driving gearhas been rotated in the second direction, the joint lever is positionedat the rear stroke end.

FIG. 58 is a plan view showing, of the constituent elements carried bythe lower chassis surface, the state in which the driving gear has beenrotated in the second direction and the joint lever has been movedforwards.

FIG. 59 is a side view showing the state in which the driving gear hasbeen rotated in the second direction and the joint lever has been movedto the forward movement stroke end.

FIG. 60 is a plan view showing the state in which the disc cartridge hasbeen ejected from the holder and in which the slider has been movedforwards.

FIG. 61 is a plan view showing, of the constituent elements carried bythe lower chassis surface, the state in which the driving gear has beenrotated in the second direction and the thrusting lug has a slidingcontact with a mating operating edge, with the operating lever havingbeen rotated.

FIG. 62 is a side view showing the state in which the thrusting lug ofthe driving gear is disengaged from the mating operating piece of thejoint lever, with the joint lever having been moved to the rear movementstroke end.

FIG. 63 is an enlarged plan view showing, of the constituent elementscarried by the lower chassis surface, the state in which the detectionby a rotation detection switch has been made and the rotation of thedriving motor ceases.

FIG. 64 is an enlarged side view, partially shown in section, andshowing the state in which manual ejection has been performed in therecording mode, as the as the position relationships between the camlever and the magnetic head.

BEST MODE FOR CARRYING OUT THE INVENTION

In the following, certain preferred embodiments of the present inventionwill be explained with reference to the drawings. The followingembodiments are directed to a disc recording and/or reproducingapparatus in which information signals are recorded on or reproducedfrom an magneto-optical disc having a diameter of approximately 64 mm,such as Mini-Disc.

A recording and/or reproducing apparatus 1, according to the presentinvention, has an outer casing 2 of a thin box shape, within whichrespective members and mechanisms as required are accommodated, as shownin FIG. 8. A horizontally elongated rectangular insertion/ejectionopening 2 a is formed in the front surface of the outer casing 2. Theouter casing 2 carries a door 3 for opening/closing theinsertion/ejection opening 2 a. If, in introducing the disc cartridge,as later explained, into the outer casing 2, the disc cartridge isejected from the outer casing 2, the door 3 is actuated to open theinsertion/ejection opening 2 a. At a preset location of the outer casing2 are arranged plural operating buttons 4 for performing variousfunctions, as shown in FIG. 8. The reproducing operation, the recordingoperation, cessation of the operation, change of sound volume, ejectionof the disc cartridge from the outer casing 2 and various editingfunctions may be carried out by actuating these operating buttons 4.

Within the outer casing 2, there is arranged a chassis 5, as shown inFIGS. 9 to 11. The chassis 5 is formed integrally by a major surfaceportion 6, side supporting portions 7, 8 arranged on left and right sideedges of the major surface portion 6, and a lever supporting portion 9as well as a lever controlling portion 10, with the lever supportingportion 9 and the lever controlling portion 10 upstanding from the rearedge of the major surface portion 6 and being spaced apart from eachother in the left and right direction, as shown in FIG. 16. A pickupmounting opening 6 a is formed towards the right side of the majorsurface portion 6, while a switch mounting opening 6 b is formed in theforward left side thereof. A retention unit mounting opening 6 c isformed towards the front right side of the major surface portion 6.Towards the right side of the major surface portion 6, positioning pins11, 11 are formed integrally in a staggered relationship in thefore-and-aft direction. Each positioning pin 11 is made up by apositioning projections 11 a and a support portion 11 b formed on therim of the positioning projections 11 a, 11 a. Towards the left side endof the major surface portion 6 are formed receptacles 12, 12 in astaggered relationship in the fore-and-aft direction. The upper surfacesof these receptacles 12, 12 are flush with the upper surfaces of thesupport portions 11 b, 11 b of the positioning pins 11, 11.

Towards the forward and rear ends of the side supporting portions 7, 8are respectively formed supporting projections 13, 14, which supportingprojections 13, 14 are formed with forwardly opening supporting grooves13 a, 14 a, respectively. On the rear sides of the rear side supportingprojections 14, 14, the side supporting portions 7, 8 are formed withlugs 15, 15, with portions lying between the supporting projections 14,14 and the lugs 15, 15 being opened upwards to serve. as guide grooves15 a, 15 a. On the upper ends of the supporting projection 14 and thelug 15 of the side supporting portion 7 on the left side, there areformed spring retention pieces 14 b, 15 b, respectively.

The lever supporting portion 9 of the chassis 5 is made up by anupstanding portion 9 a, protruded upwards from the major surface portion6, and a supporting portion 9 b protruded forwards from the upper edgeof the upstanding portion 9 a. The lever controlling portion 10 of thechassis 5 is made up by an upstanding portion 10 a, protruded upwardsfrom the major surface portion 6, and a supporting portion 10 bprotruded forwards from the upper edge of the upstanding portion 10 a.The supporting portion 10 b is formed with a control opening 10 celongated in the forward and aft direction.

A holder 16 is vertically movably supported by the side supportingportions 7, 8, as shown in FIG. 10. The holder 16 is formed of aplate-shaped elastic metal material, and is formed integrally from a topplate portion 17, side plate portions 18, 19, and support plates 20, 20,protruded from the lower edges of the side plate portions 18, 19 in adirection approaching to each other. The disc cartridge is inserted andheld in a flattened spacing defined by the top plate portion 17, sideplate portions 18, 19 and the support plates 20, 20.

In the top plate portion 17, a retention spring 17 a is segmented sothat it is slightly inclined towards its distal end. In the top plateportion 17, there is also formed a head inserting opening 17 b inregister with the pickup mounting opening 6 a of the chassis 5. Theright side end of the top plate portion 17 is formed integrally with ashift lever restoration spring 17 c which is protruded rearwards. Theleft rear end of the top plate portion 17 is formed integrally with arelief opening 17 d.

The forward ends of the side plate portions 18, 19 of the holder 16 arerespectively formed with embossed supports 18 a, 19 a which areprotruded outwards. The rear ends of the side plate portions 18, 19 areformed with outwardly protruded support pins 18 b, 19 b, respectively.The right side plate portion 19 is provided with a shutteropening/closing mechanism which is formed by a shutter restorationspring 21 and an unlock piece 22 which are formed by partiallysegmenting the side plate portion 19. The shutter restoration spring 21is protruded slightly forwards and is inclined relative to the sideplate portion 19 so that its distal end will be positioned inwardly ofthe side plate portion 19. The distal end of the shutter restorationspring 21 is bent for protruding inwards and provided as a holdingportion 21 a.

The unlock piece 22 is extended in the fore-and-aft direction so thatits major surface is directed in the up-and-down direction.

The forward end of the left side support plate 20 is formed with anoperating opening 20 a.

The top plate portion 17 of the holder 16 rotatably supports a headshift lever 23, as shown in FIGS. 10, 12 and 17. The head shift lever 23is mounted proximate to the rear end of the head inserting opening 17 band is protruded towards the head inserting opening 17 b. From the leftside edge of the head shift lever 23, a rotation controlling piece 23 aand a mating operating piece 23 b, spaced apart from each other in thefore-and-aft direction, are protruded leftwards, as shown in FIGS. 18and 19. The mating operating piece 23 b is in the form of a letter V incross-section, with the apex pointing downwards, when seen from itslateral side, as shown in FIGS. 18 and 19. The right side edge of thehead shift lever 23 is formed with the rightwardly protruded rotationcontrolling piece 23 a. The foremost part of the shift lever restorationspring 17 c provided on the top plate portion 17 of the holder 16 iselastically contacted with the right side end of the head shift lever23. As a consequence, the head shift lever 23 is biased so that itsforemost part will be moved substantially downwards.

A cam lever 24 is supported by the holder 16 for movement in thefore-and-aft direction, as shown in FIGS. 10, 12 and 13. The cam lever24 and the head shift lever 23 operate as a head movement mechanism foruplifting and lowering a magnetic head which will be explainedsubsequently.

The cam lever 24 is formed with a supported portion 25, elongated in thefore-and-aft direction, a protruding portion 26, protruded rightwardsfrom the supported portion 25 and a cam leg 27 protruded downwards fromthe supported portion 25, as shown in FIGS. 20 and 21. The supportedportion 25 has a plural number of support openings 25 a, elongated inthe fore-and-aft direction. The supporting pin 17 or the supportingpiece 17 f provided on the top plate portion 17 is inserted into thesesupport openings 25 a to permit movement in the fore-and-aft direction.A protruded portion 26 is protruded rightwards from the right side edgeof the supported portion 25 so that its foremost part is elongated inthe fore-and-aft direction. At the foremost part of the protrudedportion 26, a retention piece 28 and a cam piece 29, both of which arebent from the foremost portions of the protruded portion 26, areprovided in a spaced-apart relationship to each other. The cam piece 29is provided, looking from the rear side, with a first cam portion 29 a,a second cam portion 29 b, at a lower portion than the first cam portion29 a, and a third cam portion 29 c, at a lower portion than the secondcam portion 29 b, with the first cam portion 29 a being at substantiallythe same height level as the third cam portion 29 c. The portion of thecam leg 27 lower than a mid portion in the vertical direction is formedas a cam portion 30. This cam portion 30 is made up by an upper portion,extending from an upper position for a short length in the verticaldirection, an inclined portion 30 b, contiguous to the upper portion 30a and deflected progressively downwards towards rear and a lower portion30 c contiguous to the inclined portion 30 b and extending from theinclined position for a short length in the vertical direction.

A slider 31 is supported by the holder 16 for movement in thefore-and-aft direction, as shown in FIGS. 10, 14 and 15. The slider 31is made up by a connecting portion 32, elongated in the left and rightdirection, extensions 33, 34, protruded rearwards from the left andright ends of the connecting portion 32, and side portions 35, 36depending from the side edges of the extensions 33, 34, as shown inFIGS. 22 and 24. The left side extension 33 is provided with a springretention projection 33 a, protruded leftwards from the left side edgethereof, and a spring retention projection 33 b, protruded rightwardsfrom the right side edge thereof. A controlled piece 33 c is provided atthe rear end of the extension 33 by bending a portion of the extension33. The rear end of the extension is formed with an edge 33 d inclinedso as to be progressively deflected rightwards in the forward direction.The side portions 35, 36 are provided with supported pins 35 a, 36 a,which are spaced apart from each other in the fore-and-aft direction.The side portions 35, 36 are also provided with cam grooves 37, 38,which are spaced apart from each other in the fore-and-aft direction.The forward side cam groove 37 is formed with an upper horizontalportion 37 a, an inclined portion 37 b and a lower horizontal portion 37c, in this order, beginning from the rear side, with the upperhorizontal portion 37 a being opened rearwards. The rear side cam groove38 is formed with an upper horizontal portion 38 a, an inclined portion38 b and a lower horizontal portion 38 c, in this order, beginning fromthe rear side, with the lower horizontal portion 38 c being openedforwards. Directly at back of the cam grooves 37, 37, there is noportion of the slider 31. Here, relief openings 35 b, 36 b, openeddownwards and rearwards, are formed.

The left side portion 35 is formed with thrust pieces 35 c, 35 d,directly at back and at the rear end of the relief opening 35 b.

The slider 31 is assembled to the holder 16 as follows (see FIGS. 25 to28).

First, the slider 31 is connected to the rear side of the holder 16, asthe slider is inclined so that its forward end is positioned upwards, insuch a manner that the supporting pins 18 b, 19 b of the holder 16 willbe inserted into the cam grooves 38, 38 of the slider 31 (see FIG. 25).

The slider 31 is then moved forwardly of the holder 16 so that thesupporting pins 18 b, 19 b will be engaged in the rear ends of the camgrooves 38, 38 (see FIG. 26).

The slider 31 is then rotated relative to the holder 16 until theconnecting portion 32 rests on the top plate portion 17. Since therelief openings 35 b, 36 b are formed directly at back of the camgrooves 37, 37 of the slider 31, there is no risk of the slider 31colliding against the supporting portions 18 a, 19 a of the holder 16,such that, when the connecting portion 32 is set on the top plateportion 17, the support portions 18 a, 19 a of the holder 16 arepositioned directly at back of the upper horizontal portions 37 a, 37 aof the cam grooves 37, 37 (see FIG. 27).

Finally, the slider 31 is moved slightly rearwards relative to theholder 16 so that the support portions 18 a, 19 a are inserted andengaged in the cam grooves 37, 37 from the rear side (see FIG. 28). Thiscauses the slider 31 to be supported by the holder 16 for movement inthe fore-and-aft direction.

For assembling the slider 31 to the holder 16, it is only sufficientthat the support pins 18 b, 19 b are inserted from the forward side intothe cam grooves 38, 38 of the slider 31, the slider 31 is then rotatedrelative to the holder 16 and subsequently the slider is moved towardsrear. As a consequence, there is no necessity to provide an allowance inthe distance between the slider 31 and the holder 16 in the left andright direction corresponding to the amount of protrusion of the supportportions 18 a, 19 a and the support pins 18 b, 19 b from the side plateportions 18, 19, respectively. The result is that the width in the leftand right direction of the slider 31 may be correspondingly reduced toreduce the size of the disc recording and/or reproducing apparatus 1.

On the lever supporting portion 9 of the chassis 5, an ejection lever 39is supported for rotation, as shown in FIGS. 9 and 10. As for the slider31 and the ejection lever 39, the ejection lever 39, operating as anejection mechanism for ejecting the disc cartridge held by the holder 16from the holder 16, is formed integrally by a rotation fulcrum point 40,a control projection 41 protruded from the rotation fulcrum point 40, aprotrusion 42 extending from the rotation fulcrum point 40 in adirection substantially perpendicular to the control projection 41 andan operating portion 43 extending downwards from the distal end of theprotrusion 42, as shown in FIGS. 29 and 30. The control projection 41has its distal end edge formed as a control edge 41 a contacted with thecontrolled piece 33 c of the slider 31. A roll 44 is carried forrotation by the distal end of the control projection 41. This roll 44 iscarried as it is protruded downwards from the control projection 41. Theforward edge of the protrusion 42 has a spring retainer 42 a, while itsrear edge includes an insertion piece 42 b bent downwards. The insertionpiece 42 b is inserted into the control opening 10 c of the levercontrolling portion 10 of the chassis 5. Rotation of the ejection lever39 in a forward direction indicated by arrow R1 in FIG. 10 is controlledby the insertion piece 42 b contacting with the forward opening edge ofthe control opening 10 c.

The holder 16, carrying the cam lever 24 and the slider 31, is slidablyengaged from an inner side in guide grooves 15 a, 15 a of the sidesupporting portions 7, 8 of the chassis 5, as the support pins 18 b, 19b are protruded from the cam grooves 38, 38 of the slider 31. The slider31, carried by the holder 16, has the supported pins 35 a, 36 a slidablyengaged from the inner side in the supporting grooves 13 a, 14 a of theside supporting portions 7, 8 of the chassis 5. As a consequence, theholder 16 is movable in the vertical direction relative to the chassis 5along with the cam lever 24. The slider 31 is movable in thefore-and-aft direction relative to the holder 16, by the supportportions 18 a, 19 a and the support pins 18 b, 19 b being moved in thecam grooves 37, 38 of the slider 31 during movement of the holder 16.

When the holder 16 has been supported by the chassis 5 as describedabove, a spring member 45 as a tension coil spring is mounted undertension between the spring retainer 42 a of the ejection lever 39,rotatably carried by the lever supporting portion 9, and the springretention projection 33 b of the slider 31 (see FIG. 10). As theejection lever 39 is biased in a direction indicated by arrow R1 in FIG.10, the slider 31 is biased rearwards, with the controlled piece 33 c ofthe slider 31 being contacted with the control edge 41 a of the controlprojection 41 of the ejection lever 39, positioned at the stroke end ofrotation in the direction indicated by arrow R1 in FIG. 10, to controlthe rearward movement of the slider 31.

Between the spring retention projection 33 a of the slider 31 and thespring retention piece 14 b of the side supporting portion 7 of thechassis 5, an auxiliary spring 46, having a spring force weaker than thespring force of the spring member 45, is mounted under tension. Thisalso biases the slider 31 rearwards (see FIG. 10).

On the side supporting portion 7, a joint lever 47 is supported formovement in the fore-and-aft direction, as shown in FIGS. 9 and 10. Thejoint lever 47 is elongated in the fore-and-aft direction and is formedwith supported openings 47 a, 47 a which are spaced apart from eachother in the fore-and-aft direction (see FIG. 31). The forward loweredge of the joint lever 47 is formed with a mating operating piece 47 b,whereas the upper edge of the joint lever between the paired supportedopenings 47 a, 47 a thereof is formed with an upwardly projectingthrusting piece 47 b. A spring retainer 47 d is formed above the rearsupported opening 47 a of the joint lever 47. The rear end of the jointlever 47 is bent rightwards to form a thrusting portion 47 e. Thesupport pins 7 a, 7 a provided on the side supporting portion 7 areinserted into the supported openings 47 a, 47 a of the joint lever 47 soas to be carried for movement in the fore-and-aft direction. With thejoint lever 47 supported by the side supporting portion 7, a tensioncoil spring 48 is mounted under tension between the spring retainer 47 dand the spring retention piece 15 b of the side supporting portion 7 forbiasing the joint lever 47 rearwards.

At a mid portion of the major surface portion 6 of the chassis 5, aspindle motor, not shown, is mounted, and a disc table 49 is secured toa motor shaft of the spindle motor (see FIGS. 2 and 4). The disc table49 includes a centering boss 49 a, fitted in a center opening of adisc-shaped recording medium, and a table 49 b on which is set an innerrim of the disc-shaped recording medium. A suction magnet, not shown, isembedded in the centering boss 49 a.

Within the pickup mounting opening 6 a of the major surface portion 6,an optical pickup 50 is mounted for movement radially of the disc-shapedrecording medium, as shown in FIGS. 9 and 11. The optical pickup 50includes a biaxial actuator 52, having an objective lens 52 a, carriedon a movable base 51. The movable base 51 has its forward and rear endscarried for sliding movement by guide shafts 53, 54 mounted on the lowersurface of the major surface portion 6, respectively. A nut, not shown,provided on the movable base 51, is engaged with a lead screw 55provided on the lower surface of the major surface portion 6. The leadscrew 55 is rotated by a feed motor 56 provided on the lower surface ofthe major surface portion 6. When the lead screw 55 is rotated by thefeed motor 56, the nut meshing with the lead screw 55 is fed along theaxial direction of the lead screw 55, whereby the optical pickup 50 isguided by the guide shafts 53, 54 so as to be moved along the radius ofthe disc-shaped recording medium.

The rear end of the optical pickup 50 carries the lower surface of aU-shaped connecting member 57 with the opening of the letter U beingopened forwards when seen from the lateral side. The connecting member57 includes an intermediate portion, lying directly at back of the rearedge of the major surface portion 6, while having an upper surfaceportion lying directly above the rear end of the holder 16 (see FIG.10). On the upper surface of the connecting member 57 are mounted a headmounting arm 58 and an arm control plate 59 for controlling excessupward shifting of the head mounting arm 58 (see FIG. 10). The headmounting arm 58, formed by an elastic metal sheet of a thin thickness,is elongated in the fore-and-aft direction, and has its rear end mountedto the connecting member 57. The head mounting arm is set at a midportion thereof in the fore-and-aft direction on the head shift lever 23carried by the holder 16. A magnetic head 58 a is mounted on the forwardend of the head mounting arm 58 directly on top of the objective lens 52a of the biaxial actuator 52. The arm control plate 59 is elongated inthe fore-and-aft direction, and has its rear end mounted to theconnecting member 57 from above the head mounting arm 58. The armcontrol plate includes lateral projections for holding the head mountingarm 58 from above.

Since the optical pickup 50 and the head mounting arm 58 areinterconnected by the connecting member 57, the head mounting arm 58,carrying the optical pickup 50 and the magnetic head 58 a, may be movedin unison along the radius of the disc-shaped recording medium.

A circuit board 60 is mounted on the forward lower surface of the majorsurface portion 6 of the chassis 5, and carries plural disc detectionswitches 61 on the forward left end of the major surface portion 6 ofthe chassis 5, as shown in FIG. 9. A disc detection switch 61 is mountedvia a connection board 62, mounted in turn on the circuit board 60, andincludes a switch casing 63 and a mating operating shaft 64 verticallymovably supported on the switch casing 63, as shown in FIGS. 32 and 33.The switch casing 63 includes a rectangular bottom surface 63 a, aperipheral wall section 63 b, upstanding from the periphery of thebottom surface 63 a and an anti-extrication portion 63 c projectedinwards from the peripheral wall section 63 b. The lower end of theperipheral wall section 63 b includes contacts 63 d, 63 d. The matingoperating shaft 64 is arbor-shaped, with the diameter of a lower end 64a being thicker in thickness than the other portions. The operatingshaft includes a pair of contacts 64 b, 64 b provided on its lower end64 a. A compression spring 65 is mounted under compression between thebottom surface 63 a of the switch casing 63 and the lower surface of themating operating shaft 64, so that the mating operating shaft 64 isbiased upwards. When the mating operating shaft 64 is not acted on, thelower end 64 a is engaged with the anti-extrication portion 63 c of theswitch casing 63, thus establishing a non-detection state in which thecontacts 64 b, 64 b are not connected to the contacts 63 d, 63 d, asshown in FIG. 32. When the mating operating shaft 64 is acted on bybeing thrust downwards by the disc cartridge, the contacts 64 b, 64 bare connected to the contacts 63 d, 63 d to set up a detection state.

On the leftward lower surface portion of the circuit board 60, arotation detection switch 66 is mounted as shown in FIG. 11. A matingoperating portion 66 a of the rotation detection switch 66 is protrudedsubstantially laterally.

On the lower left surface portion of the major surface portion 6, adriving lever 67 is mounted for movement in the fore-and-aft direction,as shown in FIG. 11. The driving lever 67 is elongated in thefore-and-aft direction and is formed with supported openings 67 a, 67 aat the forward and rear ends thereof (see FIG. 34). The forward end ofthe driving lever 67 is formed with an engagement opening 67 b. In thisengagement opening 67 b is inserted and engaged the cam leg 27 of thecam lever 24. The rearward end of the driving lever 67 is formed with aconnection opening 67 c, while the mid portion thereof in thefore-and-aft direction is formed with a spring retention piece 67 d.

By the support pins 6 d, 6 d on the lower surface of the major surfaceportion 6 being inserted into the supported openings 67 a, 67 a of thedriving lever 67, and by the cam leg 27 of the cam lever 24 beinginserted and engaged with the engagement opening 67 b, the cam lever 24is moved in the fore-and-aft direction with movement of the drivinglever 67 in the fore-and-aft direction. Between the spring retentionpiece 67 d and a spring retention projection 6 e provided on the lowersurface of the major surface portion 6, a tension coil spring 68 ismounted under tension for biasing the driving lever 67 in the forwarddirection, as shown in FIG. 11.

On the lower surface of the major surface portion 6, a limit lever 69 ismounted for movement in the fore-and-aft direction, in a side-by-siderelationship to the driving lever 67, as shown in FIG. 11. The limitlever 69 is elongated in the fore-and-aft direction and is formed atforward and rear ends with supported openings 69 a, 69 a (see FIG. 35).Towards the forward end of the limit lever 69, there is provided a leversupporting portion 69 b. A support shaft 69 c is mounted in rear of thelever supporting portion 69 b. The limit lever 69 has a spring retentionopening 69 d and a forwardly directed support piece 69 e on theright-hand side and on the left-hand side of the support shaft 69 c,respectively. The limit lever 69 is formed with a thrust piece 69 f atback of the support piece 69 e, while being formed with a connectionopening 69 g towards its rear end. In the supported openings 69 a, 69 aof the limit lever 69, support pins 6 f, 6 f provided on the lowersurface of the major surface portion 6 are inserted and carried formovement in the fore-and-aft direction (see FIG. 11). A stop edge 6 gformed on the major surface portion 6 of the chassis 5 is positionedahead of the support piece 69 e of the limit lever 69 (see FIG. 11).

The driving lever 67 and the limit lever 69 are interconnected by aconversion lever 70, as shown in FIG. 11. The conversion lever 70 has acenter supported tube 70 a and upwardly projecting connection pins 70 b,70 b on both sides of the supported tube 70 a (see FIGS. 36 and 37).

A support shaft 6 h of the conversion lever 70, provided between thedriving lever 67 on the lower surface of the major surface portion 6 andthe limit lever 69, is inserted into the supported tube 70 a, forrotation relative to the major surface portion 6, as shown in FIG. 11.The connection pins 70 b, 70 b are rotatably engaged in the connectionopening 67 c of the driving lever 67 and in the connection openingconnection opening 69 g of the limit lever 69. As a result, the drivinglever 67 and the limit lever 69 are moved in the opposite directions inthe fore-and-aft direction.

The lower surface of the limit lever 69 rotatably carries an operatinglever 71, as shown in FIGS. 11 and 38. The operating lever 71 issubstantially L-shaped and has its one end formed as a rotation fulcrumpoint 71 a, which rotation fulcrum point 71 a is rotatably carried bythe lever supporting portion 69 b of the limit lever 69 (see FIGS. 38and 39). The bent portion of the operating lever 71 is formed with ashort arcuate guide opening 71 b. The support shaft 69 c of the limitlever 69 is inserted into the guide opening 71 b. The operating lever 71is rotatable relative the limit lever 69 within an extent of the guideopening 71 b.

The operating lever 71 has its distal edge bent to from a curved matingoperating edge 71 c, and includes a linear controlled edge 71 d and alinear thrust edge 71 e on both opposite sides of the mating operatingedge 71 c.

A spring retention projection 71 f is protruded from the rotationfulcrum point 71 a of the operating lever 71. A tension spring 72 ismounted under tension between the spring retention projection 71 f andthe spring retention opening 69 d of the limit lever 69. Thus, theoperating lever 71 is biased counterclockwise in the plane of FIG. 11.Except if the force in the clockwise direction in FIG. 11 is accorded tothe operating lever 71 in FIG. 11, the controlled edge 71 d is contactedwith the support piece 69 e of the limit lever 69.

A driving motor 73 is mounted on the lower surface of the major surfaceportion 6 of the chassis 5, and drives a gear set 74, made up of fourgears, carried on the lower surface of the major surface portion 6 (seeFIG. 11). A switching gear 75 meshes with the fourth gear of the gearset 74 counted from the side of the driving motor 73 (see FIG. 11). Anoperating boss 75 a is formed as one with the lower surface of theswitching gear 75. Rotation of the switching gear 75 actuates the matingoperating portion 66 a of the rotation detection switch 66 . When themating operating portion 66 a is actuated, rotation of the driving motor73 ceases transiently.

A driving gear 76 meshes with the switching gear 75. The upper surfaceof the driving gear 66 is formed with a thrusting boss 76 a (see FIG.11). The thrusting boss 76 a plays the role of a driving powertransmission for transmitting the driving power of the driving motor 73through the limit lever 69, conversion lever 70 and the driving lever 67to the cam lever 24, as a portion of the head movement mechanism, and oftransmitting the driving power of the driving motor 73 through the jointlever 47 to the slider 31 as a portion of the ejection mechanism. Thedriving gear 76 is mounted at such a position that the thrusting boss 76a is able to thrust the thrust piece 69 f of the limit lever 69, themating operating edge 71 c of the operating lever 71 and the thrust edge71 e of the operating lever 71.

A spring plate member 77, which plays the role of retaining a shutter,as later explained, of the disc cartridge, is mounted between the majorsurface portion 6 of the chassis 5 and the circuit board 60 (see FIGS. 9and 40). The spring plate member 77 has its one end 77 a mounted on themajor surface portion 6. The portion of the spring plate member towardsthe other end thereof is formed as an upwardly protruding retainer 77 b,which retainer 77 b is projected upwards through the retention unitmounting opening 6 c (see FIG. 40). The upper end of the retainer 77 bis positioned above the support portion 11 b of the positioning pin 11provided on the major surface portion 6 and the receptacle 12 (see FIG.40).

The circuit board 60 carries a controller (micro-computer) including acentral processing unit (CPU) 78 (see FIG. 41). The controller 78 sendsa control signal to each component based on a detection signal yieldedon actuation of the disc detection switch 61 and the rotation detectionswitch 66. The controller 78 also sends a control signal to eachcomponent based on an operating signal yielded on actuation of any ofthe operating buttons 4 provided on the outer casing 2.

The driving motor 73 is run in rotation or halted based on a controlsignal sent from the controller 78 through a motor driver 79. Theoptical pickup 50 is driven or halted based on a control signal sentfrom the controller 78 through an optical pickup driver 80. The feedmotor 56 and the spindle motor are also driven or halted based on thecontrol signal input from the controller 78.

The disc cartridge 120 includes a flattened rectangular box-shapedcasing 121, within which a magneto-optical disc 122 as a disc-shapedrecording medium is rotationally mounted, as shown in FIG. 8. Centrallyof the lower surface of the casing 121 is formed an insertion opening,not shown, and a through-hole, not shown, is formed laterally of theinsertion opening. In the upper surface of the casing 121, there isformed, in register with the through-hole, a head access opening 121 a,into which is inserted the magnetic head 58 a. In the casing 121 isslidably mounted a shutter 123 for opening or closing the through-holeand the head access opening 121 a. In the lateral surface of the casing121 carrying the shutter 123 is formed a groove 121 b extending in thefore-and-aft direction. In the lateral surface of the shutter 123 isformed an engagement opening 123 a. The shutter is locked by a lockmechanism, not shown, provided in the casing 121, in a state in whichthe shutter has closed the through-hole and the head access opening 121a. In the lower surface of the casing 121 are formed positioningopenings, not shown, separated from each other in the fore-and-aftdirection.

The center portion of the disc-shaped recording medium 122 is formedwith a center opening, on an opening edge of which is fitted a hubformed of a magnetic metal material.

The operation of the disc recording and/or reproducing apparatus 1 ishereinafter explained (see FIGS. 42 to 64).

First, the state prior to the loading of the disc cartridge 120 isexplained (see FIGS. 42 to 46).

The ejection lever 39 is positioned at the end of the rotational strokein the direction indicated by arrow R1 in FIG. 42. The controlled piece33 c of the slider 31 is contacted with the control edge 41 a of thecontrol projection 41, under the force of the spring member 45, forholding the slider 31 at a forward position (see FIG. 42). Thus, thesupport portions 18 a, 19 a and the support pins 18 b, 19 b of theholder 16 are engaged in the upper horizontal portions 37 a, 38 a of thecam grooves 37, 38 of the slider 31, and hence the holder 16 is held atan upper movement stroke end, that is at a position of inserting orejecting the disc cartridge 120 (see FIG. 43).

The joint lever 47, carried by the side supporting portion 7, is held atthe rear stroke end under the force of the tension coil spring 48, asshown in FIG. 7. The switching gear 75, carried by the lower surface ofthe major surface portion 6 of the chassis 5, is halted in contact withthe mating operating portion 66 a of the rotation detection switch 66,while the driving gear 76 is at a position in which the thrusting boss76 a abuts against or in proximity to the thrust piece 69 f of the limitlever 69, that is at a reference position (see FIG. 38). The limit lever69 is positioned at the rear stroke end, while the operating lever 71supported by the limit lever 69 is in such a state in which thecontrolled edge 71 d is kept in abutment against the support piece 69 eof the limit lever 69 (see FIG. 45). Since the limit lever 69 is at therear stroke end, the driving lever 67, connected to the limit lever 69through the conversion lever 70, is positioned at the forward stroke end(see FIG. 45).

Since the driving lever 67 is at the forward stroke end and the holder16 is held at the insertion/ejection position, the cam lever 24 has thelower portion 30 c of the cam leg 27 engaged in the engagement opening67 b of the driving lever 67 (see FIGS. 43 and 46). The cam lever 24 ispositioned at the forward end of the movement stroke (see FIG. 42).Thus, the head shift lever 23 is kept at a first retreat position inwhich the mating operating piece 23 b is engaged in the first cam 29 aof the cam lever 24, the head mounting arm 58 is substantially at ahorizontal position and the magnetic head 58 a is not collided againstthe disc cartridge being introduced into the holder 16 (see FIG. 46).

When the disc cartridge 120 is inserted through the insertion/ejectionopening 2 a of the outer casing 2, the door 3 is rotated, and the disccartridge 120 is inserted into the holder 16 (see FIG. 47). Theoperating portion 43 of the ejection lever 39 is thrust towards rear bythe inserted disc cartridge 120, so that the ejection lever 39 isrotated in the direction indicated by arrow R2 in FIG. 47 against theforce of the spring member 45.

As the disc cartridge 120 is inserted into the holder 16, the lateralside of the casing 121 is brought into sliding contact with the shutterrestoration spring 21, provided on the side plate portion 19 of theholder 16, so that the shutter restoration spring 21 is flexed outwards.The unlock piece 22 then is moved forwards in the groove 121 b of thedisc cartridge 120 to unlock the shutter 123. The unlock piece thenthrusts the edge of the shutter 123 to cause the sliding of the shutter123. As the shutter 123 is slid, the holding portion 21 a of the shutterrestoration spring 21 is engaged in the engagement opening 123 a of theshutter 123 to hold the disc cartridge 120 within the holder 16. As theshutter 123 is slid, the through-hole and the head access opening 121 aformed in the casing member 121 are opened.

When the disc cartridge is inserted into the holder 16, the retentionspring 17 a provided to the top plate portion 17 of the holder 16 isbrought into resilient contact with the casing member 121 of the disccartridge 120 to hold the casing member 121.

When the ejection lever 39 is rotated in the direction indicated byarrow R2 in FIG. 48 and the control edge 41 a is disengaged from thecontrolled piece 33 c of the slider 31, the slider 31 is moved rearwardsunder the force of the. spring member 45. Since the slider 31 is alsopulled rearwards by the auxiliary spring 46, mounted under tensionbetween the spring retention projection 33 a and the spring retentionpiece 14 b of the side supporting portion 7 of the chassis 5, the slider31 is positively moved to the rear movement stroke end.

When the slider 31 is moved rearwards, the roll 44 supported by theejection lever 39 rolls on the inclined edge 33 d, so that the slider 31is smoothly moved rearwards as shown in FIG. 48.

Although the auxiliary spring 46 is used in the disc recording and/orreproducing apparatus 1 of the present invention, such auxiliary spring46 may be dispensed with subject to proper adjustment of the force ofthe spring member 45. As a consequence, only the spring member 45suffices, and hence the number of components may be reduced.

With the disc recording and/or reproducing apparatus 1 of the presentinvention, the length of the extended spring member 45 is progressivelyshortened as the slider 31 is moved rearwards, as described above. Thus,the slider 31 and the ejection lever 39 may be improved in durability,and hence the load on the driving motor 73 in ejecting the disccartridge 120, as later explained is relieved to lower the powerconsumption in an amount corresponding to the diminished frictionalresistance of the slider 31 and the ejection lever 39. In addition, thespring force of the spring member 45 may be reduced due to reduction inthe load.

As the slider is moved rearwards, the support portions 18 a, 19 a andthe support pins 18 b, 19 b of the holder 16 perform relative movementfrom the upper horizontal sections 37 a, 38 a of the cam grooves 37, 38and the inclined sections 37 b, 38 b to the lower horizontal sections 37c, 38 c (see FIG. 49). Thus, the holder 16 is moved to the lower end ofthe movement stroke, as it is guided by the guide grooves 15 a, 15 aformed in the side supporting portions 7, 8, until the holder gets tothe loading position in contact with the major surface portion 6 of thechassis 5. When the holder 16 is moved downwards, the cam lever 24 isalso moved downwards, with movement of the holder 16. The cam lever 24,the lower portion 30 c of the cam leg 27 of which has been engaged inthe engagement groove 67 b of the driving lever 67, is moved through theinclined section 30 b (see FIG. 50) until the upper side section 30 a isengaged in the engagement groove 67 b, with the cam lever 24 being movedslightly rearwards relative to the holder 16 (see FIGS. 41 to 44). Theresult is that the head shift lever 23 has its mating operating piece 23b engaged in the second cam portion 29 b of the cam lever 24, so thatthe head shift lever is raised in its forward portion (see FIG. 51).Since the holder 16 has been lowered, the head mounting arm 58 has itsforward portion lowered. However, the head shift lever 23 has itsforward portion elevated, and hence the magnetic head 58 a is kept atthe second retreat position directly overlying the top plate portion 17of the holder 16 and is not introduced into the head inserting opening17 b. In terms of the relative position of the holder 16 relative to thetop plate portion 17, this second retreat position is substantially thesame as the aforementioned first retreat position.

When the holder 16 gets to the loading position corresponding to thelower end of its movement stroke, the disc table 49 is inserted via aninsertion opening of the casing member 121 of the disc cartridge 120,held by the holder 16, so that the centering boss 49 a of the disc table49 is introduced into the center opening of the disc-shaped recordingmedium 122, while the hub of the disc-shaped recording medium 122 issucked by a magnet provided on the centering boss 49 a, whereby thedisc-shaped recording medium 122 is loaded on the disc table 49.

When the holder 16 is moved downwards, the operating shafts 64, 64, 64of the disc detection switches 61, 61, 61 are thrust and actuated by thecasing member 101 of the disc cartridge 120 for use for write protectdetection, AD/MD-DATA2 (trademark) detection and disc reflectancedetection, that is for detection whether the disc is a ROM (optical disccarrying information signals as pits) or a RAM (magneto-optical disc). Aloading detection switch for detecting whether the disc-shaped recordingmedium 122 has been loaded on the disc table 49 is provided as aseparate unit, even though such loading detection switch is not shown.Alternatively, the disc detection switch 61 may be used to detect thatthe disc-shaped recording medium 122 has been loaded on the disc table49.

When the disc-shaped recording medium 122 has been loaded on the disctable 49, the inner edge of the disc-shaped recording medium 122 is seton the table portion 49 b, while the disc-shaped recording medium 122 ispositioned at a location slightly above the inner lower surface of thecasing member 121.

When the disc-shaped recording medium 122 has been loaded on the disctable 49, the positioning projections 11 a, 11 a of the positioning pins11, 11 provided on the major surface portion 6 of the chassis 5 areintroduced into the positioning openings of the casing member 121 forpositioning the disc cartridge 120 relative to the chassis 5. Wen thedisc cartridge 100 has been positioned relative to the chassis 5, thecasing member 121 is set on the support portion 11 a of the positioningpin 11 and on the receptacle 12 (see FIG. 52). The retainer 77 b of thespring plate member 77, mounted on the lower surface of the majorsurface portion 6, is brought into resilient contact with the shutter123 of the disc cartridge 120 at this time from the lower side (see FIG.52). Consequently, the vibrations of the shutter 123 during thereproduction and recording of the disc-shaped recording medium 122 canbe suppressed to assure optimum reproducing and recording operations.

Since the spring plate member 77 for suppressing the vibrations of theshutter 123 is mounted on the chassis 5 arranged within the outer casing2, the vibrations otherwise transmitted from outside to the discrecording and/or reproducing apparatus 1 can scarcely be transmittedthrough the spring plate member 77 to the shutter 123 to suppress thevibrations efficiently and sufficiently.

Moreover, since the spring plate member 77, having its one end 77 amounted on the major surface portion 6 of the chassis 5, is used asretention means for holding the shutter 123 to suppress its vibrations,the vibrations to the shutter 123 may be effectively prohibited by asimplified structure, such that provision of retention means does notraise the cost.

In the foregoing description, the spring plate member 77 is used asretention means. Alternatively, the disc detection switch 61 may also beused as retention means in place of the spring plate member 77 (see FIG.53). In this case, the disc detection switch 61 is arranged on thecircuit board 60 at such a position that the mating operating shaft 64is projected upwards from the retention unit mounting opening 6 c formedin the major surface portion 6, in place of arranging the disc detectionswitch 61 provided at the left end of the circuit board 60.

When the holder 16 is lowered, the mating operating shaft 64 is broughtinto resilient abutting contact from below against the shutter 123 ofthe disc cartridge 120, under the spring force of the compression coilspring 65, to suppress the vibrations of the shutter 123. At the sametime, the loading of the disc-shaped recording medium 22 on the disctable 49 is detected by the operation on the mating operating shaft 64.Thus, if the disc detection switch 61 is used as retention means,suppression of vibrations of the shutter 123 and the above detection canbe achieved simultaneously, so that there is no necessity of providingdedicated retention means in addition to the disc detection switch 61,thus achieving reduction in the number of component parts and in cost.

As the retention means, the spring plate member 77 and the discdetection switch 61 may be used in combination.

If, when the holder 16 carrying the disc cartridge 120 is lowered andthe disc-shaped recording medium 122 has been loaded on the disc table49, a replay button (operating button) 4, provided on the outer casing2, is actuated, the disc table 49 and hence the disc-shaped recordingmedium 122 are run in rotation by the driving of the spindle motor,while the optical pickup 50 is guided by the guide shafts 53, 54 by thedriving of the feed motor 56 and hence is moved radially of thedisc-shaped recording medium 122. At this time, a laser light beam isilluminated from the objective lens 52 a of the biaxial actuator 52 ofthe optical pickup 50 through the through-hole of the casing member 121to the disc-shaped recording medium 122 to reproduce informationsignals.

If a stop button (operating button) 4 is actuated, the rotation of thedisc table 49 is halted, while the optical pickup 50 ceases to beoperated to stop the reproduction of the information signals.

If, as the holder 16 carrying the disc cartridge 120 is lowered so thatthe disc-shaped recording medium 122 is loaded on the disc table 49, arecording button (operating button) 4 provided on the outer casing 2 isactuated, so that the driving motor 73 and hence the gear set 74 are runin rotation in one direction. When the gear set 74 is run in rotation,the switching gear 75 is run in rotation, so that the driving gear 76meshing with the switching gear is run in rotation in one direction,with the consequence that the thrusting boss 76 a of the g76 thrusts thethrust edge 71 e of the operating lever 71 forwards (see FIG. 54).

When the thrust edge 71 e of the operating lever 71 is thrust, since thecontrolled edge 71 d is contacted with the support piece 69 e of thelimit lever 69, positioned at the rear end of the movement stroke, thesupport piece 69 e is thrust forwards by the controlled edge 71 d tocause forward movement of the limit lever 69 (see FIG. 54). When thelimit lever 69 is moved forwards, the driving lever 67, positioned atthe forward end of the movement stroke, is moved rearwards by therotational movement of the conversion lever 70 (see FIG. 54). By therearward movement of the driving lever 67, the cam lever 24, the upperside portion 30 a of which is engaged in the engagement opening 67 b, ismoved towards rear with respect to the holder 16 (see FIG. 55).

The limit lever 69, moved forwards, is moved to the forward end of itsmovement stroke, as a result of the contact of the support piece 69 ewith the stop edge 6 g formed on the major surface portion 6. At thistime, the rotation of the driving motor 73 ceases, so that the drivinglever 67 is halted at the rear end of its movement stroke (see FIG. 54).When the driving lever 67 is halted at the rear end of its movementstroke, the cam portion 30 of the cam lever 24 has been moved to a pointat back of the mating operating piece 23 b of the head shift lever 23,such that the head shift lever 23 is held at the lower end of itsrotational movement, with the controlling piece 23 a in contact with theopening edge of the head inserting opening 17 b of the holder 16.Consequently, the head mounting arm 58 is inclined so that its forwardend is lowered (see FIG. 55). The magnetic head 58 a is introduced intothe holder 16 through the head inserting opening 17 b into contact withthe disc-shaped recording medium 122 through the head access opening 121a formed in the casing member 121 of the disc cartridge 120. One of therotation controlling pieces 23 a of the head shift lever 23 ispositioned below the retention piece 28 of the cam lever 24 and isretained by the retention piece 28.

With continued driving of the spindle motor, the disc table 49 is run inrotation, while the optical pickup 50 is guided by the guide shafts 53,54, by the driving of the feed motor 56, so as to be moved radially ofthe disc-shaped recording medium 102. At this time, a laser light beamis illuminated from the objective lens 52 a of the biaxial actuator 52of the optical pickup 50 through the through-hole of the casing member121 to the disc-shaped recording medium 122, at the same time as amagnetic field is applied through the magnetic head 58 a to thedisc-shaped recording medium 122, to record information signals.

If a stop button (operating button) 4, among the operating buttons 4, isactuated, the driving motor 73 is rotated in an opposite direction tothat in the previous operation to run the gear set 74 and the switchinggear 75 into rotation. The driving gear 76 is run in rotation in asecond direction so that the thrust piece 69 f of the limit lever 69 isthrust rearwards by the thrusting boss 76 a of the driving gear 76 (seeFIG. 56). When the thrust piece 69 f of the limit lever 69 is thrust,the limit lever 69 and the operating lever 71 are moved rearwards inunison, while the driving lever 67, located at the rear end of themovement stroke, is moved forwards by the rotational movement of theconversion lever 70 (see FIG. 56). By the forward movement of thedriving lever 67, the cam lever 24, the upper side portion 30 a of whichis engaged in the engagement opening 67 b, is moved forwards relative tothe holder 16.

When the mating operating portion 66 a of the rotation detection switch66 is actuated by the operating boss 75 a of the switching gear 75, astop signal is input to the driving motor 73, so that the operation ofthe driving motor 73 ceases. The limit lever 69 is halted when it hasbeen moved to the rear end of the movement stroke, while the drivinglever 67 is halted at the forward end of its movement stroke (see FIG.56). The driving gear 76 is reverted to its reference position.

When the driving lever 67 is halted at the forward movement stroke end,the mating operating piece 23 b of the head shift lever 23 is engagedwith the second cam portion 29 b of the cam lever 24, the magnetic head58 a is moved upwards from the head inserting opening 17 b of the holder16, and the magnetic head 58 a is kept at the second retreat positiondirectly overlying the top plate portion 17 of the holder 16 (see FIG.50). Simultaneously, the rotation of the disc table 49 is halted toterminate the operation of recording the information signals.

When the stop button (operating button) 4 is operated to terminate thereproducing or recording operation, as described above, the drivinglever 67 is positioned at the forward movement stroke end, while thelimit lever 69 is located at the rear movement stroke end (see FIG. 56)and the joint lever 47 is at the rear movement stroke end (see FIG. 57).

If, when the reproducing or recording operation is finished, theejection button, as one of the operating buttons 4, is actuated, thedriving motor 73 is rotated in the opposite direction. When the drivingmotor 73 is rotated in the opposite direction, the driving gear 76 isrotated in the second direction, and the mating operating piece 47 b ofthe joint lever 47 is thrust forwards, with the joint lever 47 beingthen moved forwards against the bias of the tension coil spring 48 (seeFIG. 58).

When the joint lever 47 is moved forwards, the thrust piece 35 c of theslider 31 is thrust forwards by a thrusting piece 47 c, with the slider31 being moved forwards (see FIG. 59). When the slider 31 is movedforwards, the support portions 18 a, 19 a and the support pins 18 b, 19b of the holder 16 perform relative movement from the lower horizontalportions 37 c, 38 c of the cam grooves 37, 38 through the inclinedportions 37 b, 38 b to the upper horizontal portions 37 a, 38 a (seeFIG. 43). Consequently, since the support pins 18 b, 19 b of the holder16 guided by the guide groove 15 a formed in the side supportingportions 7, 8 of the chassis 5 are elevated, while the disc cartridge120 held by the holder 16 is elevated along with the holder 16, thedisc-shaped recording medium 122 is unloaded from the disc table 49.

When the holder 16 is elevated with the forward movement of the slider31, the cam lever 24, the upper side portion 30 a of which has beenengaged in the engagement opening 67 b of the of the driving lever 67,has the lower side portion 30 c engaged in the engagement opening 67 b.The cam lever 24 is moved forwards relative to the holder 16 a distanceequal to the distance between the upper side portion 30 a and the lowerside portion 30 c in the fore-and-aft direction. Consequently, the headshift lever 23 has the mating operating piece 23 b engaged in the firstcam portion 29 a of the cam lever 24, with the head mounting arm 58being substantially in the horizontal position (see FIG. 46). Withforward movement of the slider 31, the spring member 45 is extended toincrease the biasing force of the ejection lever 39 in the directionindicated by arrow R1 in FIG. 46. When the ejection lever 39 is rotatedclockwise, as the roll 44 rolls on the inclined edge 33 d of the slider31, and the control edge 41 a is spaced apart from the controlled piece33 c, the ejection lever 39 is rotated significantly clockwise under theforce of the spring member 45, such that the ejection lever 39 isrotated in the direction indicated by arrow R1 in FIG. 60 until theinsertion piece 42 b is brought into contact with the forward openingedge of the control opening 10 c of the lever supporting portion 9provided to the chassis 5. At this time, the holder 16 has been rotatedto the insertion/ejection position. When the ejection lever 39 isrotated in the direction indicated by arrow R1 in FIG. 60, the casingmember 21 of the disc cartridge 120 is thrust forwards by the operatingportion 43, so that a portion of the disc cartridge 100 is ejected fromthe holder 16.

When the disc cartridge 120 is ejected from the holder 16, the holder 21a of the shutter restoration spring 21 is engaged in the engagementopening 123 a of the shutter 123, so that the shutter 123 is slid tostop up the through-hole and the head access opening 121 a formed in thecasing member 121. The through-hole and the head access opening 121 aare closed.

The driving gear 76 continues to be rotated and the thrusting boss 76 ais disengaged from the mating operating piece 47 b of the joint lever 47into engagement with the mating operating edge 71 c of the operatinglever 71 (see FIG. 61). Since the mating operating piece 47 b of thejoint lever 47 is disengaged from the thrusting boss 76 a, the jointlever 47 is moved to the rear movement stroke end under the bias of thetension coil spring 48 (see FIG. 62).

When the thrusting boss 76 a of the driving gear 76 is engaged with theoperated edge 71 c of the operating lever 71, the operating lever 71 isrotated, with rotation of the driving gear 76, against the bias of thetension spring 72, such that the thrusting boss 76 a is bought intsliding contact with the mating operating edge 71 c (see FIG. 61).

As the driving gear 76 further continues its rotation, the thrustingboss 76 a is disengaged from the mating operating edge 71 c of theoperating lever 71. The operating lever 71 is rotated under the bias ofthe tension spring 72 to return to a state in which the controlled edge71 d is contacted with the support piece 69 e of the limit lever 69 (seeFIG. 63). The switching gear 75 is also run in rotation by rotation ofthe driving motor 73. When the operating boss 75 a acts on the matingoperating portion 66 a of the rotation detection switch 66, a stopsignal is input to the driving motor 73 to stop the rotation of thedriving motor 73 (see FIG. 63). The driving gear 76 is returned to itsreference position.

The disc cartridge 120, ejected from the holder 16, is partiallyprotruded via the insertion/ejection opening 2 a of the outer casing 2.The protruded portion may be gripped and extracted to take out the disccartridge 120.

When taking out the disc cartridge 120, the unlock piece 22 provided onthe side plate portion 19 of the holder 16 is moved rearwards in thegroove 101 b of the disc cartridge 120 by relative movement. The shutter123 is again locked by a lock mechanism.

With the disc recording and/or reproducing apparatus 1 of the presentinvention, described above, the driving gear 76, run in rotation by thedriving power transmitted from the driving motor 73, is rotated in thefirst direction to lower the magnetic head 58 a to set up a stateenabling the recording operation of information signals. The drivinggear 76 is run in rotation in the second direction opposite to the firstdirection to perform the ejecting operation of the disc cartridge 120.Thus, when both the head movement mechanism and the ejection mechanismare operated by the driving motor 73, there is no necessity ofcontinuously moving one of the driving lever 67 and the joint lever 47in the same direction to actuate the head movement mechanism and theejection mechanism, the movement stroke of the driving lever 67 and thatof the joint lever 47 may be correspondingly reduced to enable the sizeof the disc recording and/or reproducing apparatus to be reduced.

The disc recording and/or reproducing apparatus 1 of the presentinvention is provided with the operating lever 71 which operates thelimit lever 69, using the thrusting boss 76 a operating as the drivingpower transmitting portion, when the driving motor 73 is rotated in onedirection, and which is receded from the trajectory of the thrustingboss 76 a when the driving motor 73 is rotated in the other direction.Consequently, the operating lever 71 does not obstruct rotation of thedriving gear 76 when the driving motor 73 is rotated in the oppositedirection to actuate the ejection mechanism, so that the operation ofthe disc recording and/or reproducing apparatus 1 may be optimum.

In addition, with the disc recording and/or reproducing apparatus 1,since there is provided the rotation detection switch 66 which detectsthe end of the operation of the ejection mechanism and the end of theoperation of the head movement mechanism, it is unnecessary to provide adedicated switch detecting the state of completion of the operation,from one mechanism to another, thus enabling the number of componentparts to be reduced.

The manual ejection operation for the disc cartridge 120 is nowexplained. The manual ejection operation in the disc recording and/orreproducing apparatus 1 may be classed into an ejection operation in thestop mode in which the recording or reproduction for the disc-shapedrecording medium 122 has come to a close, an ejection operation in thereplay mode and an ejection operation in the recording mode. It is whenfor example the driving motor 73 has ceased its operation due to batterydown that the manual ejection operation is needed.

In the operation in any of these three modes, the joint lever 47 ismoved forwards by manual operation to eject the disc cartridge 120. Theforward movement of the joint lever 47 may be achieved by for exampleinserting a pin into an insertion opening, not shown, formed in the backside of the outer casing 2, to thrust the thrusting portion 47 e fromrear side.

First, the operation of the manual ejection operation in the stop andreplay modes and the ejecting operation during reproduction for thedisc-shaped recording medium 122 are explained. These two operations areaccomplished by moving the joint lever 47 forwards as the matingoperating piece 23 b of the head shift lever 23 is engaged in the secondcam portion 29 b of the cam lever 24, as shown in FIG. 44.

When the joint lever 47 is moved forwards, the thrust piece 35 c of theslider 31 is thrust forwards by the thrusting piece 47 c, such that thesupport portions 18 a, 19 a and the support pins 18 b, 19 b of theholder 16 perform relative movement from the lower horizontal portions37 c, 38 c of the cam grooves 37, 38 through the inclined portions 37 b,38 b to the upper horizontal portions 37 a, 38 a (see FIG. 43).Consequently, the holder 16 is elevated to unload the disc-shapedrecording medium 122 from the disc table 49.

When the holder 16 is elevated, the lower side portion 30 c of the camlever 24 is engaged in the engagement opening 67 b, such that the camlever 24 is moved forwards relative to the holder 16 by a distancecorresponding to the distance between the upper side portion 30 a andthe lower side portion 30 c in the fore-and-aft direction. Thus, thehead shift lever 23, the mating operating piece 23 b of which has beenengaged in the second cam portion 29 b of the cam lever 24, now has themating operating piece 23 b engaged in the first cam portion 29 b of thecam lever 24, with the head mounting arm 58 then being in substantiallythe horizontal position (see FIG. 46).

As the slider 31 is moved forwards, the spring member 45 is extended.When the control edge 41 a is separated from the controlled piece 33 c,the ejection lever 39 is rotated appreciably in the direction indicatedby arrow R1, under the force of the spring member 45. The casing member121 of the disc cartridge 100 is thrust forwards significantly by theoperating portion 43 to eject the disc cartridge 120 from the holder 16(see FIG. 60).

The disc cartridge 120, ejected from the holder 16, is partiallyprotruded via the insertion/ejection opening 2 a of the outer casing 2.The protruded portion may be gripped and extracted to take out the disccartridge 120.

The operation of manual ejection in the recording mode is now explained.This operation is carried out by causing forward movement of the jointlever 47, as the mating operating piece 23 b of the head shift lever 23is located ahead of the cam portion 30 of the cam lever 24, as shown inFIG. 55. When the joint lever 47 is moved forwards, the thrust piece 35c of the slider 31 is thrust forwards, by the thrusting piece 47 c, sothat the support portions 18 a, 19 a and the support pins 18 b, 19 b ofthe holder 16 perform relative movement from the lower horizontalportions 37 c, 38 c of the cam grooves 37, 38 through the inclinedportions 37 b, 38 b to the upper horizontal portions 37 a, 38 a (seeFIG. 43). Consequently, the holder 16 is elevated to unload thedisc-shaped recording medium 122 from the disc table 49.

When the holder 16 is elevated, the lower side portion 30 c of the camlever 24 is engaged in the engagement opening 67 b, such that the camlever 24 is moved forwards relative to the holder 16 by a distancecorresponding to the distance between the upper side portion 30 a andthe lower side portion 30 c in the fore-and-aft direction. Thus, thehead shift lever 23, the mating operating piece 23 b of which has beenengaged in the second cam portion 29 b of the cam lever 24, now has themating operating piece 23 b engaged in the third cam portion 29 c of thecam lever 24, with the head mounting arm 58 then being in substantiallythe horizontal state (see FIG. 64). As the head mounting arm 58 is atsubstantially the horizontal position, the magnetic head 58 a isuplifted from the head inserting opening 17 b of the holder 16. Themagnetic head 58 a is moved upwards from the head inserting opening 17 bof the holder 16 and is held at a third retreat position directlyoverlying the top plate portion 17 of the holder 16. The disc cartridge120 may now be ejectable without contacting with the magnetic head 58 a(see FIG. 64). This third retreat position, as the relative position ofthe holder 16 with respect to the top plate portion 17, is substantiallythe same as the first and second retreat positions described above. Withforward movement of the slider 31, the spring member 45 is extended.When the control edge 41 a is separated from the controlled piece 33 c,the ejection lever 39 is rotated appreciably in the direction indicatedby arrow R1, under the spring force of the spring member 45. The casingmember 121 of the disc cartridge 120 is thrust forwards by the operatingportion 43 to eject the disc cartridge 120 from the holder 16 (see FIG.60). The disc cartridge 120 ejected from the holder 16 is partiallyprotruded from the insertion/ejection opening 2 a of the outer casing 2,so that the disc cartridge 120 can be taken out by gripping and pullingthe protruded portion outwards.

Thus, in the recording mode, the cam lever 24 is moved forwards toretreat the magnetic head 58 a to above the disc cartridge 120 beingejected and to hold the magnetic head 58 a at the third retreat positionto achieve the ejecting operation without damaging the magnetic head 58a.

With the disc recording and/or reproducing apparatus 1, according to thepresent invention, the magnetic head 58 a is held at the first, secondor third retreat position, for which the position relationships of theholder to the top plate portion 17 are substantially the same, exceptduring the recording operation, when the disc cartridge 120 is held onthe holder 16. Consequently, the spacing of movement of the magnetichead 58 a between the upper surface of the outer casing 2 and the topplate portion 17 can be minimized to allow to reduce the thickness ofthe disc recording and/or reproducing apparatus 1.

Moreover, with the disc recording and/or reproducing apparatus 1,according to the present invention, the cam lever 24 is provided withthe inclined portion 30 b slidably engaged in the engagement opening 67b of the driving lever 67 and, when the cam lever 24 is uplifted orlowered with the uplifting or descent of the holder 16, the engagingposition of the inclined portion 30 b in the engagement opening 67 b ischanged to cause the cam lever 24 to be moved in the fore-and-aftdirection with respect to the holder 16. Thus, it is sufficient toprovide the inclined portion 30 b for causing movement of the cam lever24 relative to the holder 16 to simplify the structure or mechanism forejection to realize positive ejection without increasing the cost.

In the disc recording and/or reproducing apparatus 1 according to thepresent invention, the recording head used is the magnetic head 58 a.This, however, is merely illustrative, and any of recording headsconsistent with the recording system for a recording medium, such as anoptical head or a magneto-optical disc, may be used as the recordinghead.

The shape or structure of the various components, indicated in theabove-described embodiments, are given only by way of examples inpracticing the invention, and should not be construed in the sense oflimiting the present invention.

INDUSTRIAL APPLICABILITY

With the disc recording and/or reproducing apparatus according to thepresent invention, in which the spring member is provided between theejection lever and the slider and the ejection lever is biased by thisspring member in a direction of ejecting the recording medium from theholder, and in which the slider is also biased in the direction ofintroducing the recording medium, the mechanism of ejecting therecording medium may be simplified to reduce the number of componentparts of the overall apparatus.

Moreover, with the disc recording and/or reproducing apparatus accordingto the present invention, in which the relative positions of the head,contacted with and separated away from the recording medium, and theholder, with respect to the contacting or separating direction, issubstantially constant for the first retreat position receded from therecording medium held by the holder, the second retreat position recededfrom the recording medium during reproduction of the information signalsand for the third retreat position receded from the recording mediumbeing ejected from the holder, the spacing of movement of the magnetichead between the outer casing and the holder may be minimized to reducethe thickness of the overall apparatus.

In addition, with the disc recording and/or reproducing apparatusaccording to the present invention, in which the ejection mechanism orthe head movement mechanism is operated depending on the direction ofrotation of the driving gear, rotated in one or the opposite directionby the driving motor, the ejection mechanism and the head movementmechanism can be simplified to reduce the size of the apparatus.

Furthermore, with the disc recording and/or reproducing apparatusaccording to the present invention, in which, when the disc housed inthe disc cartridge is loaded on the disc table, the shutter provided onthe disc cartridge opened by the shutter opening/closing mechanism isretained by the retention mechanism, the shutter may undergo vibrationsduring the disc reproducing or recording operation only to a lesserextent for assuring stabilized recording and/or reproduction ofinformation signals.

1. A recording medium driving device for driving a disc cartridgeincluding a disc and a cartridge having said disc held therein, saiddisc cartridge opening/closing an information recording surface of saiddisc by a shutter movably mounted in said cartridge, said driving devicecomprising: readout means movable along a radius of said disc forreading out information from said information recording surface of saiddisc; a chassis on which said readout means is mounted for movementradially of said disc; a holder movably mounted on said chassis forholding said disc cartridge; a disc table for loading said disc in saiddisc cartridge held by said holder; a shutter opening/closing mechanismfor opening/closing said shutter of said cartridge; and retention meansprovided on one of said chassis and said holder for holding said shutteropened by said shutter opening/closing mechanism when said disc isloaded on said disc table.
 2. The recording medium driving deviceaccording to claim 1 wherein said retention means comprises a springplate member having one end mounted on said chassis and including at another end a retainer resiliently contacted with said shutter.
 3. Therecording medium driving device according to claim 1 wherein saidretention means comprises a detection switch having an operated shaftresiliently contacted with said shutter when said holder is moved, saidoperated shaft being operated by resilient contact thereof with saidshutter to detect whether writing on said information recording surfaceof said disc is inhibited.
 4. The recording medium driving deviceaccording to claim 1 wherein said retention means comprises a detectionswitch having an operated shaft resiliently contacted with said shutterwhen said holder is moved, said operated shaft being operated byresilient contact thereof with said shutter to detect a type of saiddisc.
 5. The recording medium driving device according to claim 1wherein said retention means comprises a detection switch having anoperated shaft resiliently contacted with said shutter when said holderis moved, said operated shaft being operated by resilient contactthereof with said shutter to detect whether said disc has been loaded onsaid disc table.
 6. The recording medium driving device according toclaim 1 wherein said readout means includes an optical pickup forilluminating laser light on said disc.